Currently, the computer starts and operates fine. However, seconds after an ethernet cable is plugged in (I'm assuming anytime it gets an active internet connection), the monitor turns white, with strange blue lines running through it, and the computer freezes. Dead stop. Or, it may keep operating in the background, but considering your computer looks like it's running some kind of DirectX video test, it might as well be dead.
Originally, the computer would not turn on. Or, it wouldn't turn on with the internet plugged in, which we found out after trying some things. Once it was booted (with no ethernet plugged in, obviously), if the ethernet was plugged back in, the computer would restart. Hard restart, by the way, not a "Windows is shutting down." Also, the computer would freeze (Explorer goes "Not Responding") whenever a USB Storage Device (iPod) was plugged in. The drivers installed fine, but as soon as that sucker was plugged in, BAM, instant freeze.
I eventually installed the newest version of AVG 8 (this all happened two weekends ago), and ran a scan on the system. It found several 'Malware' alerts, and I got rid of them, obviously. This is when the computer stopped doing a hard reboot when the ethernet was plugged in, and just went to the Weird White Screen. I'm not sure if the iPod will still make it freeze at this point.
So... HELP? I have no idea what to do with this. It's the weirdest thing I've seen in 10 years of being "that computer guy". But yea, if anyone could lend some assistance, it would be most appreciated!